JPWO2013161984A1 - Diamine, polymer, liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element - Google Patents

Abstract

It is set as the diamine characterized by being represented by following formula (1). [In the formula (1), X1 is a single bond or an alkylene group having 1 to 6 carbon atoms (provided that —CH2— which is not adjacent to the alkylene group is replaced by an ether bond, an ester bond or an amide bond). X2 is —OCO—CH═CH— or —CH═CH—COO—, X3 is a single bond, an alkylene group having 1 to 10 carbon atoms or a divalent benzene ring, and X4 Is a single bond, —OCO—CH═CH— or —CH═CH—COO—, and X 5 is a single bond or an alkylene group having 1 to 6 carbon atoms (provided that —CH 2 − not adjacent to the alkylene group is (It may be replaced by an ether bond, an ester bond, or an amide bond, provided that the formula (1) has one or more cinnamoyl groups.)

Description

  The present invention relates to a novel diamine, polyimide precursor, polyimide and polyamide, liquid crystal aligning agent, liquid crystal alignment film, and liquid crystal display element.

  In the liquid crystal display element, the liquid crystal alignment film plays a role of aligning the liquid crystal in a certain direction. Currently, the main liquid crystal alignment films that are used industrially are polyimide precursors such as polyamic acid (also called polyamic acid), polyamic acid esters, and polyimide-based liquid crystal aligning agents composed of polyimide solutions. It is manufactured by applying and forming a film. Further, when the liquid crystal is horizontally aligned, parallel aligned, or inclinedly aligned with respect to the substrate surface, after the film formation, a surface stretching process by rubbing is further performed. As an alternative to the rubbing treatment, a method using an anisotropic photochemical reaction by irradiation with polarized ultraviolet rays or the like has been proposed, and in recent years, studies for industrialization have been performed.

  In order to improve the display characteristics of such liquid crystal display elements, methods such as changing the structure of polyamic acid, polyamic acid ester and polyimide, polyamic acid with different characteristics, blend of polyamic acid ester and polyimide, adding additives, etc. As a result, improvements in liquid crystal alignment and electrical characteristics, control of the pretilt angle, and the like are performed. For example, it has been proposed to use a polymer having a group having a specific structure as a side chain (see Patent Document 1).

JP-T-2001-517719

  However, performance enhancement of liquid crystal display elements, increase in area, power saving of display devices, etc. have progressed, and characteristics required for liquid crystal alignment films have become severe. However, there is still a problem that the image sticking property is insufficient and the liquid crystal alignment performance is changed by AC (alternating current) driving to cause an afterimage.

  An object of the present invention is to solve the above-described problems of the prior art, and an object of the present invention is to provide a liquid crystal display element having a good afterimage characteristic by reducing a change in liquid crystal alignment performance of a liquid crystal alignment film by AC driving. To do. That is, a polyimide precursor that constitutes a liquid crystal display element having such characteristics, a novel diamine capable of obtaining a liquid crystal alignment film having polyimide or polyamide, and a liquid crystal alignment agent and a liquid crystal display element using the same are provided. The purpose is to provide.

  As a result of diligent research, the present inventors have achieved the above object by a polyimide precursor using a specific diamine represented by the following formula (1) as a diamine component, a liquid crystal aligning agent containing polyimide or polyamide. Therefore, the present invention has been found to be extremely effective, and the present invention has been completed. In addition, the diamine represented by the following formula (1) is a novel compound not yet described in the literature.

That is, the present invention has the following gist.
1. A diamine represented by the following formula (1):

（式（１）中、Ｘ^１は単結合または炭素数１〜６のアルキレン基（但し、該アルキレン基の隣り合わない−ＣＨ_２−は、エーテル結合、エステル結合またはアミド結合に置き換わっていてもよい）であり、Ｘ^２は−ＯＣＯ−ＣＨ＝ＣＨ−または−ＣＨ＝ＣＨ−ＣＯＯ−であり、Ｘ^３は単結合、炭素数１〜１０のアルキレン基または２価のベンゼン環であり、Ｘ^４は単結合、−ＯＣＯ−ＣＨ＝ＣＨ−または−ＣＨ＝ＣＨ−ＣＯＯ−であり、Ｘ^５は単結合または炭素数１〜６のアルキレン基（但し、該アルキレン基の隣り合わない−ＣＨ_２−は、エーテル結合、エステル結合またはアミド結合に置き換わっていてもよい）である。但し、式（１）中には、１つ以上のシンナモイル基を有する。）

(Equation (1), X ¹ is a single bond or an alkylene group having 1 to 6 carbon atoms (, -CH 2 nonadjacent of the alkylene group _- an ether bond, be replaced in an ester bond or an amide bond X ² is —OCO—CH═CH— or —CH═CH—COO—, X ³ is a single bond, an alkylene group having 1 to 10 carbon atoms, or a divalent benzene ring, ⁴ is a single bond, —OCO—CH═CH— or —CH═CH—COO—, and X ⁵ is a single bond or an alkylene group having 1 to 6 carbon atoms (provided that —CH _{2 is} not adjacent to the alkylene group). -May be replaced by an ether bond, an ester bond or an amide bond, provided that the formula (1) has one or more cinnamoyl groups.)

2. A polymer characterized in that it is at least one selected from a polyimide precursor obtained using the diamine according to 1, a polyimide obtained by imidizing the polyimide precursor, and polyamide.

3. 2. A liquid crystal aligning agent comprising the polymer described in 2.

4). A liquid crystal alignment film obtained by using the liquid crystal aligning agent according to 3.

5. A liquid crystal display element comprising the liquid crystal alignment film according to claim 4.

  ADVANTAGE OF THE INVENTION According to this invention, the novel diamine which can obtain the liquid crystal aligning film by which the change of the liquid crystal aligning performance by AC drive was reduced can be provided. And since the liquid crystal aligning film obtained by using this diamine is hard to change the liquid crystal aligning performance by AC drive, the liquid crystal display element which has this liquid crystal aligning film has an effect that an afterimage is hard to generate | occur | produce.

The present invention is described in detail below.
The diamine of the present invention is a diamine represented by the above formula (1). In formula (1), the cinnamoyl group is a structure represented by the following formula.

In the formula (1), the position of the amino group (—NH ₂ ) of the benzene ring is not particularly limited. From the viewpoint of liquid crystal alignment performance and ease of synthesis, for example, —X ¹ —X ² — It is preferable to exist in the para position or the meta position with respect to X ³ -X ⁴ -X ^5- .

  Examples of the diamine represented by the formula (1) include the following diamines.

（式中、Ｘは独立して単結合もしくはエーテル（−Ｏ−）、エステル（−ＣＯＯ−または−ＯＣＯ−）及びアミド（−ＣＯＮＨ−または−ＮＨＣＯ−）から選択される結合基であり、Ｙは独立して単結合または炭素数１〜５のアルキレン基であり、Ｚは独立して炭素数１〜１０のアルキレン基もしくはフェニレン基である。ベンゼン環上のアミノ基の結合位置や、中央のベンゼン環に対する結合基の位置は特に限定されない。）

Wherein X is independently a single bond or a linking group selected from ether (—O—), ester (—COO— or —OCO—) and amide (—CONH— or —NHCO—); Is independently a single bond or an alkylene group having 1 to 5 carbon atoms, Z is independently an alkylene group having 1 to 10 carbon atoms or a phenylene group, the bonding position of the amino group on the benzene ring, (The position of the linking group with respect to the benzene ring is not particularly limited.)

  Specific examples of the diamine represented by the formula (1) include the following diamines.

  A liquid crystal alignment film formed using a liquid crystal aligning agent containing a polyimide precursor such as polyamic acid and polyamic acid ester, polyimide and polyamide using the diamine of the present invention represented by the above formula (1) as a raw material Is a change in liquid crystal alignment performance due to AC (alternating current) driving, for example, a change in liquid crystal alignment orientation. Therefore, the liquid crystal display element having this liquid crystal alignment film has a stable liquid crystal alignment performance of the liquid crystal alignment film in AC driving, so that an afterimage is hardly generated by AC driving, that is, an afterimage characteristic by AC driving is very good. There is an effect. Moreover, the liquid crystal aligning film formed using the diamine represented by the said Formula (1) is excellent also in liquid crystal aligning performance itself, and can be made into a thing without an alignment defect substantially.

Thus, by using the diamine represented by the above formula (1) of the present invention, a liquid crystal alignment film in which a change in liquid crystal alignment performance due to AC driving is reduced, and an afterimage is hardly generated by AC driving. The reason for this is not necessarily clear, but it is represented by the formula (1) that can impart orientation to the liquid crystal to the main chain of the polyimide precursor, polyimide or polyamide using the diamine represented by the formula (1). By introducing a specific photoreactive group derived from diamine (ie, —HN—C ₆ H ₄ —X ¹ —X ² —X ³ —X ⁴ —X ⁵ —C ₆ H ₄ —NH—) Even if the liquid crystal is moved by AC driving, it is presumed that the specific photoreactive group derived from diamine represented by the formula (1) is difficult to move and the orientation direction is difficult to shift.

  On the other hand, for example, in the present invention, the structure derived from the diamine represented by the formula (1) introduced into the main chain of the polyimide precursor, polyimide or polyamide is a side chain instead of the main chain of the polyimide precursor, polyimide or polyamide. In this case, since the side chain is hung from the main chain, when the AC drive is performed, the side chain moves by being pressed against the liquid crystal moved by the AC drive, and the formula (1 This is because the structure derived from the diamine represented by) moves, and the orientation direction is greatly shifted by AC driving, and an afterimage is likely to be generated by AC driving.

  The method for synthesizing the diamine represented by the above formula (1) is not particularly limited, and can be produced, for example, according to the synthesis examples described later. For example, if it is diamine represented by Formula (a), it is compoundable by the method shown below.

  The diamine represented by the above formula (a) can be obtained by synthesizing a corresponding dinitro compound represented by the following formula (a ′), further reducing the nitro group and converting it to an amino group. The method for reducing the dinitro compound is not particularly limited, and usually palladium-carbon, platinum oxide, Raney nickel, iron, tin chloride, platinum black, rhodium-alumina, platinum carbon sulfide and the like can be used as a catalyst. From the viewpoint of selectively reducing only the nitro group with high yield while leaving the olefin unreduced, it is effective to use a chemical reduction method using iron or tin chloride. Examples of the solvent include a solvent such as ethyl acetate, toluene, tetrahydrofuran, dioxane, and alcohol, and examples of the reducing agent include a reaction using hydrogen gas, hydrazine, hydrogen chloride, ammonium chloride, and the like.

（式中、Ｘ及びＹは、それぞれ式（ａ）におけるＸ及びＹと同じである。）

(In the formula, X and Y are the same as X and Y in formula (a), respectively).

  The method for synthesizing the dinitro compound represented by the formula (a ′) is not particularly limited, and can be synthesized by any method, and specific examples thereof include, for example, the method shown in the following reaction. can do.

  In this reaction, the nitrobenzene compound A and the compound B having a carboxylic acid are reacted with each other in a direct condensation method using, for example, DMAP / DCC or DMAP / EDC in an organic solvent, or the carboxylic acid is converted to thionyl chloride or chloride. It can be synthesized by reacting it as an acid chloride using oxalyl, phosphoryl chloride, sulfuryl chloride, phosphorus trichloride and the like. DMAP is 4-N, N-dimethylaminopyridine, DCC is dicyclohexylcarbodiimide, and EDC is 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride.

  In the nitrobenzene compound A, X and Y are the same as X and Y in the formula (a), respectively, for example, 4-nitrophenol, 3-nitrophenol, 2-nitrophenol, 4-nitrobenzyl alcohol, 3-nitro Examples include benzyl alcohol, 2-nitrobenzyl alcohol, 4-nitrophenethyl alcohol, 3-nitrophenethyl alcohol, 2-nitrophenethyl alcohol and the like, and a linking group Y is inserted between the benzene ring and the hydroxyl group as necessary. May be. Further, other substituents may be bonded on the benzene ring, and the substitution position of the nitro group on the benzene ring is appropriately selected from those at which the target diamine is obtained. In addition, the compound shown here is an example and is not specifically limited.

  Examples of the organic solvent include solvents that do not affect the reaction, specifically, aromatic solvents such as toluene and xylene, aliphatic hydrocarbon solvents such as hexane and heptane, and halogens such as dichloromethane and 1,2-dichloroethane. Solvent, ether solvents such as tetrahydrofuran and 1,4-dioxane, aprotic polar solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, or a mixture thereof It can also be used. Moreover, these usage-amounts are arbitrary.

  Other diamines can also be synthesized by using the same technique as the diamine represented by the above formula (a).

  The polyimide precursors such as polyamic acid and polyamic acid ester of the present invention are obtained by reacting a diamine component containing a diamine represented by the above formula (1) with a tetracarboxylic acid component. In addition, polyamic acid ester is obtained also by the method of converting the carboxyl group of polyamic acid into ester. And the polyimide of this invention is obtained by imidating polyimide precursors, such as these polyamic acid or polyamic acid ester. Moreover, the polyamide of this invention reacts the diamine component containing the diamine represented by the said Formula (1), and the halide of dicarboxylic acid in presence of a base, or contains the diamine represented by the said Formula (1). It can be obtained by reacting a diamine component with a dicarboxylic acid in the presence of a suitable condensing agent and base. Any of polyimide precursors such as polyamic acid and polyamic acid ester, polyimide, and polyamide are useful as a polymer for obtaining a liquid crystal alignment film. In addition, the diamine represented by the formula (1) contained in the diamine component may be one kind or two or more kinds, and the diamine component is one kind of diamine other than the diamine represented by the formula (1). Or two or more types may be included.

  The diamine represented by the above formula (1) can exhibit the effects of the present invention at 10 mol% or more with respect to the total amount of the diamine component, but is preferably 30 to 100 mol%, more preferably 50. ˜100 mol%. In the present specification, unless otherwise specified, the ratio is based on the number of moles.

  Moreover, as other diamines other than the diamine represented by the above formula (1) that may be contained in the diamine component, p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2 , 5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4 -Diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diaminobiphenyl, 3,3'-dimethyl-4 , 4′-diaminobiphenyl, 3,3′-dimethoxy-4,4′-diaminobiphenyl, 3,3′- Hydroxy-4,4′-diaminobiphenyl, 3,3′-dicarboxy-4,4′-diaminobiphenyl, 3,3′-difluoro-4,4′-biphenyl, 3,3′-trifluoromethyl-4 , 4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 4,4'-diaminodiphenylmethane, 3,3 '-Diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'- Diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3'-di Minodiphenyl ether, 4,4′-sulfonyldianiline, 3,3′-sulfonyldianiline, bis (4-aminophenyl) silane, bis (3-aminophenyl) silane, dimethyl-bis (4-aminophenyl) silane, Dimethyl-bis (3-aminophenyl) silane, 4,4′-thiodianiline, 3,3′-thiodianiline, 4,4′-diaminodiphenylamine, 3,3′-diaminodiphenylamine, 3,4′-diaminodiphenylamine, 2 , 2′-diaminodiphenylamine, 2,3′-diaminodiphenylamine, N-methyl (4,4′-diaminodiphenyl) amine, N-methyl (3,3′-diaminodiphenyl) amine, N-methyl (3,4) '-Diaminodiphenyl) amine, N-methyl (2,2'-diaminodiphenyl) ) Amine, N-methyl (2,3′-diaminodiphenyl) amine, 4,4′-diaminobenzophenone, 3,3′-diaminobenzophenone, 3,4′-diaminobenzophenone, 1,4-diaminonaphthalene, 2, 2'-diaminobenzophenone, 2,3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diaminonaphthalene, 2 , 6-Diaminonaphthalene, 2,7-diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis (4-aminophenyl) ethane, 1,2-bis (3-aminophenyl) ethane, 1,3- Bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, 1,4-bis 4-aminophenyl) butane, 1,4-bis (3-aminophenyl) butane, bis (3,5-diethyl-4-aminophenyl) methane, 1,4-bis (4-aminophenoxy) benzene, 1, 3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 1,4-bis (4-aminobenzyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4 ′-[1,4-phenylenebis (methylene)] dianiline, 4,4 ′-[1,3-phenylenebis (methylene)] dianiline, 3 , 4 '-[1,4-phenylenebis (methylene)] dianiline, 3,4'-[1,3-phenylenebis (methylene)] dianiline, 3,3 '-[1,4-phenylenebi (Methylene)] dianiline, 3,3 ′-[1,3-phenylenebis (methylene)] dianiline, 1,4-phenylenebis [(4-aminophenyl) methanone], 1,4-phenylenebis [(3- Aminophenyl) methanone], 1,3-phenylenebis [(4-aminophenyl) methanone], 1,3-phenylenebis [(3-aminophenyl) methanone], 1,4-phenylenebis (4-aminobenzoate) 1,4-phenylenebis (3-aminobenzoate), 1,3-phenylenebis (4-aminobenzoate), 1,3-phenylenebis (3-aminobenzoate), bis (4-aminophenyl) terephthalate, bis (3-aminophenyl) terephthalate, bis (4-aminophenyl) isophthalate, bis (3-aminopheny L) Isophthalate, N, N '-(1,4-phenylene) bis (4-aminobenzamide), N, N'-(1,3-phenylene) bis (4-aminobenzamide), N, N'- (1,4-phenylene) bis (3-aminobenzamide), N, N ′-(1,3-phenylene) bis (3-aminobenzamide), N, N′-bis (4-aminophenyl) terephthalamide, N, N′-bis (3-aminophenyl) terephthalamide, N, N′-bis (4-aminophenyl) isophthalamide, N, N′-bis (3-aminophenyl) isophthalamide, 9,10-bis (4-aminophenyl) anthracene, 4,4′-bis (4-aminophenoxy) diphenylsulfone, 2,2′-bis [4- (4-aminophenoxy) phenyl] propane, 2 2'-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2'-bis (4-aminophenyl) hexafluoropropane, 2,2'-bis (3-aminophenyl) hexafluoropropane 2,2′-bis (3-amino-4-methylphenyl) hexafluoropropane, 2,2′-bis (4-aminophenyl) propane, 2,2′-bis (3-aminophenyl) propane, , 2′-bis (3-amino-4-methylphenyl) propane, 1,3-bis (4-aminophenoxy) propane, 1,3-bis (3-aminophenoxy) propane, 1,4-bis (4 -Aminophenoxy) butane, 1,4-bis (3-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) pentane, 1,5-bis (3-amino) Phenoxy) pentane, 1,6-bis (4-aminophenoxy) hexane, 1,6-bis (3-aminophenoxy) hexane, 1,7-bis (4-aminophenoxy) heptane, 1,7- ( 3-aminophenoxy) heptane, 1,8-bis (4-aminophenoxy) octane, 1,8-bis (3-aminophenoxy) octane, 1,9-bis (4-aminophenoxy) nonane, 1,9- Bis (3-aminophenoxy) nonane, 1,10- (4-aminophenoxy) decane, 1,10- (3-aminophenoxy) decane, 1,11- (4-aminophenoxy) undecane, 1,11- ( 3-aminophenoxy) undecane, 1,12- (4-aminophenoxy) dodecane, 1,12- (3-aminophenoxy) dodecane, 4- (aminomethyl) Aromatic diamines such as aniline, 3- (aminomethyl) aniline, 3-((aminomethyl) methyl) aniline, 4- (2-aminoethyl) aniline or 3- (2-aminoethylaniline), bis (4- Cycloaliphatic diamines such as aminocyclohexyl) methane or bis (4-amino-3-methylcyclohexyl) methane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diamino Examples include aliphatic diamines such as hexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, or 1,12-diaminododecane. It is done.

  The above-mentioned other diamines can be used alone or in combination of two or more depending on the properties such as liquid crystal orientation, voltage holding ratio, and accumulated charge when the liquid crystal alignment film is used.

  The tetracarboxylic acid component is at least one selected from tetracarboxylic acids and tetracarboxylic acid derivatives. Examples of the tetracarboxylic acid derivative include tetracarboxylic acid dihalide, tetracarboxylic dianhydride, tetracarboxylic acid diester dichloride, and tetracarboxylic acid diester. For example, a polyamic acid can be obtained by reacting a diamine component with a tetracarboxylic acid dihalide, tetracarboxylic dianhydride, or the like. In addition, a polyamic acid ester can be obtained by reacting a tetracarboxylic acid diester dichloride with a diamine component or reacting a tetracarboxylic acid diester with a diamine component in the presence of a suitable condensing agent or base. The tetracarboxylic acid component may be one type or two or more types.

  Examples of the tetracarboxylic acid component include a tetracarboxylic dianhydride represented by the following formula (3).

（式（３）中、Ｚ_１は炭素数４〜６の非芳香族環状炭化水素基を含有する炭素数４〜１３の４価の有機基である。）

(In the formula (3), _{Z 1} is a tetravalent organic group having 4 to 13 carbon atoms which contains a non-aromatic cyclic hydrocarbon group having 4 to 6 carbon atoms.)

In formula (3), specific examples of Z ₁ include tetravalent organic groups represented by the following formulas (3a) to (3j).

（式（３ａ）中、Ｚ_２〜Ｚ_５は水素原子、メチル基、塩素原子またはベンゼン環であり、それぞれ、同じであっても異なってもよく、式（３ｇ）中、Ｚ_６およびＺ_７は水素原子またはメチル基であり、それぞれ、同じであっても異なってもよい。）

(In the formula (3a), Z _{2 to} Z ₅ are a hydrogen atom, a methyl group, a chlorine atom or a benzene ring, and may be the same or different. In the formula (3g), Z ₆ and Z ₇ Are hydrogen atoms or methyl groups, which may be the same or different.

In formula (3), particularly preferred structure of Z ₁ is represented by formula (3a), formula (3c), formula (3d), formula (3e), formula (3f) or formula because of polymerization reactivity and ease of synthesis. (3g). Among these, the formula (3a), the formula (3e), the formula (3f), or the formula (3g) is preferable.

  Moreover, the ratio of the tetracarboxylic dianhydride shown by Formula (3) with respect to the tetracarboxylic acid component whole quantity is not specifically limited, For example, the tetracarboxylic dianhydride whose tetracarboxylic acid component is shown by the said Formula (3) It may be only. Of course, the tetracarboxylic acid component may contain a tetracarboxylic acid or a tetracarboxylic acid derivative other than the tetracarboxylic dianhydride represented by the formula (3) as long as the effects of the present invention are not impaired. In that case, it is preferable that 1 mol% or more of the total amount of the tetracarboxylic acid component is the tetracarboxylic dianhydride represented by the above formula (3), more preferably 5 mol% or more, and still more preferably 10 mol%. That's it.

  Other tetracarboxylic dianhydrides other than the tetracarboxylic dianhydride represented by the above formula (3) include pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6 -Naphthalene tetracarboxylic acid, 1,4,5,8-naphthalene tetracarboxylic acid, 2,3,6,7-anthracene tetracarboxylic acid, 1,2,5,6-anthracene tetracarboxylic acid, 3,3 ', 4,4′-biphenyltetracarboxylic acid, 2,3,3 ′, 4-biphenyltetracarboxylic acid, bis (3,4-dicarboxyphenyl) ether, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid Bis (3,4-dicarboxyphenyl) sulfone, bis (3,4-dicarboxyphenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane 1,1,1,3,3,3-hexafluoro-2,2-bis (3,4-dicarboxyphenyl) propane, bis (3,4-dicarboxyphenyl) dimethylsilane, bis (3,4- Dicarboxyphenyl) diphenylsilane, 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis (3,4-dicarboxyphenyl) pyridine, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic Acid, 3,4,9,10-perylenetetracarboxylic acid or 1,3-diphenyl-1,2,3,4-cyclobutanetetracarboxylic acid.

Tetracarboxylic acid diesters are not particularly limited. Specific examples are given below.
Specific examples of the aliphatic tetracarboxylic acid diester include 1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1 , 3-Dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2, 3,4-cyclopentanetetracarboxylic acid dialkyl ester, 2,3,4,5-tetrahydrofurantetracarboxylic acid dialkyl ester, 1,2,4,5-cyclohexanetetracarboxylic acid dialkyl ester, 3,4-dicarboxy-1 -Cyclohexyl succinic acid dialkyl ester, 3,4-dicarboxy- , 2,3,4-Tetrahydro-1-naphthalene succinic acid dialkyl ester, 1,2,3,4-butanetetracarboxylic acid dialkyl ester, bicyclo [3,3,0] octane-2,4,6,8- Tetracarboxylic acid dialkyl ester, 3,3 ′, 4,4′-dicyclohexyltetracarboxylic acid dialkyl ester, 2,3,5-tricarboxycyclopentylacetic acid dialkyl ester, cis-3,7-dibutylcycloocta-1,5- Diene-1,2,5,6-tetracarboxylic acid dialkyl ester, tricyclo [4.2.1.0 ^2,5 ] nonane-3,4,7,8-tetracarboxylic acid-3, 4: 7,8 A dialkyl ester, hexacyclo [6.6.0.1 ^2,7 . 0 ^3,6 . 1 ^9,14 . 0 ^10,13] hexadecane -4,5,11,12- tetracarboxylic acid-4,5: 11,12-dialkyl ester, 4- (2,5-di-oxo-tetrahydrofuran-3-yl) -1,2, Examples include 3,4-tetrahydronaphthalene-1,2-dicarboxylic dialkyl ester.

  As the aromatic tetracarboxylic acid dialkyl ester, pyromellitic acid dialkyl ester, 3,3 ′, 4,4′-biphenyltetracarboxylic acid dialkyl ester, 2,2 ′, 3,3′-biphenyltetracarboxylic acid dialkyl ester, 2,3,3 ′, 4-biphenyltetracarboxylic acid dialkyl ester, 3,3 ′, 4,4′-benzophenone tetracarboxylic acid dialkyl ester, 2,3,3 ′, 4-benzophenone tetracarboxylic acid dialkyl ester, bis (3,4-dicarboxyphenyl) ether dialkyl ester, bis (3,4-dicarboxyphenyl) sulfone dialkyl ester, 1,2,5,6-naphthalene tetracarboxylic acid dialkyl ester, 2,3,6,7- Naphthalene tetracarboxylic acid dialkyl ester And the like.

  There are no particular limitations on the dicarboxylic acid that is reacted with the diamine component to obtain the polyamide of the present invention. Specific examples of the dicarboxylic acid or its derivative aliphatic dicarboxylic acid to be reacted with the diamine component to obtain polyamide include malonic acid, succinic acid, dimethylmalonic acid, succinic acid, fumaric acid, glutaric acid, adipic acid, muconic acid, 2 -Dicarboxylic acids such as methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3,3-diethylsuccinic acid, azelaic acid, sebacic acid and suberic acid.

  Examples of the alicyclic dicarboxylic acid include 1,1-cyclopropanedicarboxylic acid, 1,2-cyclopropanedicarboxylic acid, 1,1-cyclobutanedicarboxylic acid, 1,2-cyclobutanedicarboxylic acid, and 1,3-cyclobutanedicarboxylic acid. Acid, 3,4-diphenyl-1,2-cyclobutanedicarboxylic acid, 2,4-diphenyl-1,3-cyclobutanedicarboxylic acid, 1-cyclobutene-1,2-dicarboxylic acid, 1-cyclobutene-3,4-dicarboxylic acid Acid, 1,1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,1-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexane Dicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,4- (2-norbo Nene) dicarboxylic acid, norbornene-2,3-dicarboxylic acid, bicyclo [2.2.2] octane-1,4-dicarboxylic acid, bicyclo [2.2.2] octane-2,3-dicarboxylic acid, 2, 5-dioxo-1,4-bicyclo [2.2.2] octanedicarboxylic acid, 1,3-adamantane dicarboxylic acid, 4,8-dioxo-1,3-adamantane dicarboxylic acid, 2,6-spiro [3. 3] Heptanedicarboxylic acid, 1,3-adamantanediacetic acid, camphoric acid and the like.

  As aromatic dicarboxylic acids, o-phthalic acid, isophthalic acid, terephthalic acid, 5-methylisophthalic acid, 5-tert-butylisophthalic acid, 5-aminoisophthalic acid, 5-hydroxyisophthalic acid, 2,5-dimethylterephthalic acid Acid, tetramethylterephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-anthracenedicarboxylic acid, 1,4 Anthraquinone dicarboxylic acid, 2,5-biphenyl dicarboxylic acid, 4,4'-biphenyl dicarboxylic acid, 1,5-biphenylene dicarboxylic acid, 4,4 "-terphenyl dicarboxylic acid, 4,4'-diphenylmethane dicarboxylic acid, 4,4'-diphenylethanedicarboxylic acid, 4,4'-diphenyl Rupropanedicarboxylic acid, 4,4'-diphenylhexafluoropropanedicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 4,4'-bibenzyldicarboxylic acid, 4,4'-stilbene dicarboxylic acid, 4,4'- Transdicarboxylic acid, 4,4′-carbonyldibenzoic acid, 4,4′-sulfonyldibenzoic acid, 4,4′-dithiodibenzoic acid, p-phenylenediacetic acid, 3,3′-p-phenylenedipropion Acid, 4-carboxycinnamic acid, p-phenylenediacrylic acid, 3,3 ′-[4,4 ′-(methylenedi-p-phenylene)] dipropionic acid, 4,4 ′-[4,4 ′-( Oxydi-p-phenylene)] dipropionic acid, 4,4 ′-[4,4 ′-(oxydi-p-phenylene)] butyric acid, (isopropylidenedi-p-phenylenedioxy) Can be exemplified a two-butyric acid, bis (p- carboxyphenyl) dicarboxylic acids such as dimethyl silane.

  Examples of the dicarboxylic acid containing a heterocyclic ring include 1,5- (9-oxofluorene) dicarboxylic acid, 3,4-furandicarboxylic acid, 4,5-thiazole dicarboxylic acid, 2-phenyl-4,5-thiazole dicarboxylic acid, 1,2,5-thiadiazole-3,4-dicarboxylic acid, 1,2,5-oxadiazole-3,4-dicarboxylic acid, 2,3-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid, 2, Examples thereof include 5-pyridinedicarboxylic acid, 2,6-pyridinedicarboxylic acid, 3,4-pyridinedicarboxylic acid, and 3,5-pyridinedicarboxylic acid.

  The various dicarboxylic acids may be acid dihalides or those having an anhydrous structure. These dicarboxylic acids are preferably dicarboxylic acids that can give a polyamide having a linear structure, from the viewpoint of maintaining the orientation of liquid crystal molecules. Among these, terephthalic acid, isoterephthalic acid, 1,4-cyclohexanedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, 4,4′-diphenylmethanedicarboxylic acid, 4,4′-diphenylethanedicarboxylic acid, 4,4 '-Diphenylpropanedicarboxylic acid, 4,4'-diphenylhexafluoropropanedicarboxylic acid, 2,2-bis (phenyl) propanedicarboxylic acid, 4,4 "-terphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2 , 5-pyridinedicarboxylic acid or these acid dihalides, etc. Some of these compounds have isomers, but may be a mixture containing them. In addition, the dicarboxylic acids used in the present invention are exemplified in the above exemplified compounds. It is not limited.

  The tetracarboxylic dianhydride represented by the above formula (3), other tetracarboxylic acids and tetracarboxylic acid derivatives, dicarboxylic acids, and the like are liquid crystal alignment properties, voltage holding ratios, accumulated charges, etc. when used as liquid crystal alignment films. Depending on the desired characteristics, one kind or a mixture of two or more kinds may be used.

  The reaction of the diamine component and the tetracarboxylic acid component is usually performed in an organic solvent. The organic solvent used at that time is not particularly limited as long as the generated polyimide precursor such as polyamic acid dissolves. Specific examples include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, dimethyl sulfoxide, tetramethyl urea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, γ- Butyrolactone, isopropyl alcohol, methoxymethylpentanol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, Ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol Nobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl Ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol Methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dioxane, n-hexane , N-pentane, n-octane, diethyl ether, cyclohexanone, ethylene carbonate, propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, pyruvate Ethyl, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-metho Shipuropion acid, 3-methoxy propionic acid propyl, 3-methoxy propionic acid butyl, and the like diglyme or 4-hydroxy-4-methyl-2-pentanone. These may be used alone or in combination. Furthermore, even if it is a solvent which does not dissolve a polyimide precursor, you may mix and use the said solvent in the range which the produced | generated polyimide precursor does not precipitate. Moreover, since the water | moisture content in an organic solvent inhibits a polymerization reaction, and also causes the produced polyimide precursor to hydrolyze, it is preferable to use what dehydrated and dried the organic solvent.

  When the diamine component and the tetracarboxylic acid component are reacted in an organic solvent, the solution in which the diamine component is dispersed or dissolved in the organic solvent is stirred, and the tetracarboxylic acid component is dispersed or dissolved in the organic solvent as it is. And a method of adding a diamine component to a solution obtained by dispersing or dissolving a tetracarboxylic acid component in an organic solvent, a method of alternately adding a tetracarboxylic acid component and a diamine component, and the like. Any of these methods may be used. In addition, when reacting using a plurality of diamine components or tetracarboxylic acid components, they may be reacted in a premixed state, individually or sequentially, or further individually reacted low molecular weight substances. May be mixed and reacted. Although the polymerization temperature in that case can select the arbitrary temperature of -20 degreeC-150 degreeC, Preferably it is the range of -5 degreeC-100 degreeC. The reaction can be carried out at any concentration, but if the concentration is too low, it is difficult to obtain a high molecular weight polyimide precursor (and thus polyimide), and if the concentration is too high, the viscosity of the reaction solution becomes too high. Uniform stirring becomes difficult. Therefore, the concentration of the total amount of the diamine component and the tetracarboxylic acid component is preferably 1 to 50% by mass, more preferably 5 to 30% by mass in the reaction solution. The initial stage of the reaction is carried out at a high concentration, and then an organic solvent can be added.

  In the polymerization reaction of a polyimide precursor such as polyamic acid, the ratio of the total number of moles of the diamine component to the total number of moles of the tetracarboxylic acid component is preferably 0.8 to 1.2. Similar to a normal polycondensation reaction, the molecular weight of the polyimide precursor produced increases as the molar ratio approaches 1.0.

  The polyamic acid ester can be obtained by reacting the tetracarboxylic acid diester dichloride with the diamine component as described above, or reacting the tetracarboxylic acid diester with the diamine component in the presence of an appropriate condensing agent or base. it can. Alternatively, it can also be obtained by previously synthesizing a polyamic acid by the above method and esterifying the carboxyl group of the polyamic acid using a polymer reaction.

  Specifically, for example, tetracarboxylic acid diester dichloride and a diamine component are present in the presence of a base and an organic solvent at −20 ° C. to 150 ° C., preferably 0 ° C. to 50 ° C., for 30 minutes to 24 hours, preferably 1 By reacting for 4 to 4 hours, a polyamic acid ester can be synthesized.

  As the base, pyridine, triethylamine, and 4-dimethylaminopyridine can be used, but pyridine is preferable because the reaction proceeds gently. The addition amount of the base is preferably 2 to 4 times the molar amount of the tetracarboxylic acid diester dichloride from the viewpoint of easy removal and high molecular weight.

  Further, when polycondensation of a tetracarboxylic acid diester and a diamine component in the presence of a condensing agent, as a base, triphenyl phosphite, dicyclohexylcarbodiimide, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride, N, N′-carbonyldiimidazole, dimethoxy-1,3,5-triazinylmethylmorpholinium, O- (benzotriazol-1-yl) -N, N, N ′, N′-tetramethyluronium Tetrafluoroborate, O- (benzotriazol-1-yl) -N, N, N ′, N′-tetramethyluronium hexafluorophosphate, (2,3-dihydro-2-thioxo-3-benzoxa Zolyl) phosphonic acid diphenyl, 4- (4,6-dimethoxy-1,3,5-triazin-2-yl And 4-methoxy mol ho potassium chloride n- hydrate can be used.

  In the method using the condensing agent, the reaction proceeds efficiently by adding Lewis acid as an additive. As the Lewis acid, lithium halides such as lithium chloride and lithium bromide are preferable. The addition amount of the Lewis acid is preferably 0.1 to 1.0 times the molar amount of the diamine or tetracarboxylic acid diester to be reacted.

  The solvent used in the above reaction can be the same solvent as that used in the synthesis of the polyamic acid shown above. However, N-methyl-2-pyrrolidone, γ -Butyrolactone is preferable, and these may be used alone or in combination. The concentration at the time of synthesis is such that in the reaction solution of a tetracarboxylic acid derivative such as tetracarboxylic acid diester dichloride or tetracarboxylic acid diester and a diamine component, from the viewpoint that polymer precipitation is difficult to occur and a high molecular weight product is easily obtained. The total concentration is preferably 1 to 30% by mass, and more preferably 5 to 20% by mass. Moreover, in order to prevent hydrolysis of tetracarboxylic acid diester dichloride, the solvent used for the synthesis of the polyamic acid ester is preferably dehydrated as much as possible, and it is preferable to prevent mixing of outside air in a nitrogen atmosphere.

  The polyimide precursor thus polymerized is, for example, a polymer having a repeating unit represented by the following formula [a].

（式［ａ］中、Ｒ_１１は、原料のテトラカルボン酸成分に由来する４価の有機基であり、Ｒ_１２は、原料のジアミン成分に由来する２価の有機基であり、Ａ_１１およびＡ_１２は、水素原子または炭素数１〜４のアルキル基であり、それぞれ同じであっても異なってもよく、ｊは正の整数を示す。）

(In the formula [a], R ₁₁ is a tetravalent organic group derived from the raw material tetracarboxylic acid component, R ₁₂ is a divalent organic group derived from the raw material diamine component, and A ₁₁ and A ₁₂ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, which may be the same or different, and j represents a positive integer.)

In the above formula [a], each of R ₁₁ and R ₁₂ may be one type and a polymer having the same repeating unit, or R ₁₁ and R ₁₂ may be a plurality of types and a polymer having a repeating unit having a different structure. But you can.

In the above formula [a], R ₁₁ is a group derived from a tetracarboxylic acid component represented by the following formula [c] or the like which is a raw material. In addition, when R ₁₂ is a group derived from a diamine component represented by the following formula [b], which is a raw material, for example, R ₁₂ is a group derived from a diamine represented by the above formula (1), —C ₆ H ^{_{4 -X 1 -X 2 -X 3 -X}} 4 -X 5 -C 6 H 4 - is. Note that, as shown in the above formula [a], by a diamine represented by the above formula (1) as a raw material, _-HN-C 6 in the main chain ^{H 4 -X 1 -X 2 -X 3} -X _⁴ -X ⁵ -C ₆ H ⁴ -NH- is a polyimide precursor that is introduced.

（式［ｂ］および式［ｃ］中、Ｒ_１１およびＲ_１２は、式［ａ］で定義したものと同じである。）

(In formula [b] and formula [c], R ₁₁ and R ₁₂ are the same as defined in formula [a].)

  And a polyimide is obtained by carrying out dehydration ring closure of such a polyimide precursor.

  Examples of the method for imidizing the polyimide precursor include thermal imidization in which the polyimide precursor solution is heated as it is or catalyst imidization in which a catalyst is added to the polyimide precursor solution.

  The temperature at which the polyimide precursor is thermally imidized in the solution is 100 ° C. to 400 ° C., preferably 120 ° C. to 250 ° C., and is preferably performed while removing water generated by the imidization reaction from the system.

  The catalyst imidation of the polyimide precursor can be performed by adding a basic catalyst and an acid anhydride to the polyimide precursor solution and stirring at -20 to 250 ° C, preferably 0 to 180 ° C. The amount of the basic catalyst is 0.5 to 30 mol times, preferably 2 to 20 mol times of the amidic acid group, and the amount of the acid anhydride is 1 to 50 mol times, preferably 3 to 30 mol of the amido acid group. Is double. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Among them, pyridine is preferable because it has a basicity appropriate for advancing the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, pyromellitic anhydride, and the like. Among them, use of acetic anhydride is preferable because purification after completion of the reaction is facilitated. The imidization rate by catalytic imidation can be controlled by adjusting the amount of catalyst, reaction temperature, and reaction time.

  In addition, what is necessary is just to throw a reaction solution into a solvent and to precipitate, when collect | recovering the produced | generated polyimide precursors and a polyimide from polyimide precursors, such as polyamic acid and polyamic acid ester, and the reaction solution of a polyimide. Examples of the solvent used for precipitation include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, and water. The polyimide precursor or polyimide that has been deposited in a solvent and collected can be collected by filtration, and then dried at normal temperature or under reduced pressure at room temperature or by heating. Moreover, the polyimide precursor and polyimide which collect | recovered and collect | recovered are redissolved in an organic solvent, and the operation which carries out reprecipitation collection | recovery is repeated 2 to 10 times, The impurity in a polyimide precursor or a polyimide can be decreased. Examples of the solvent at this time include alcohols, ketones, and hydrocarbons, and it is preferable to use three or more kinds of solvents selected from these because purification efficiency is further increased.

  The dehydration cyclization rate (imidation rate) of the amic acid group of polyimide does not necessarily need to be 100%, and can be arbitrarily selected in the range of 0% to 100% depending on the application and purpose. % Is preferred.

  Polyamide can also be synthesized in the same manner as the polyamic acid ester.

  The molecular weight of the polyimide precursor, polyimide or polyamide of the present invention is determined by GPC (Gel) in consideration of the strength of the resulting polymer film (liquid crystal alignment film), workability when forming the polymer film, and uniformity of the polymer film. The weight average molecular weight measured by the Permeation Chromatography method is preferably 5,000 to 1,000,000, and more preferably 10,000 to 150,000.

  The liquid crystal aligning agent of this invention contains polyimide precursors, such as the said polyamic acid and polyamic acid ester, a polyimide, and polyamide. A liquid crystal aligning agent is a solution for forming a liquid crystal aligning film, and is a solution in which a polymer component for forming a liquid crystal aligning film is dispersed or dissolved in an organic solvent. The liquid crystal alignment film is a film for aligning liquid crystals in a predetermined direction. And in this invention, the said polymer component contains at least 1 type selected from polyimide precursors, such as the said polyamic acid of this invention, polyamic acid ester, a polyimide, and polyamide.

  In the liquid crystal aligning agent of the present invention, all of the polymer components contained may be polyimide precursors such as the polyamic acid and polyamic acid ester of the present invention, polyimide or polyamide, and the polyamic acid of the present invention. Other polymers may be mixed with a polyimide precursor such as polyamic acid ester, polyimide or polyamide. When another polymer is contained as the polymer component, the content of the other polymer in the total amount of the polymer component is 0.5% by mass to 50% by mass, preferably 1% by mass to 30% by mass.

  As such other polymers, for example, only a diamine other than the diamine represented by the above formula (1) of the present invention is used as a diamine component to be reacted with a tetracarboxylic dianhydride component or a dicarboxylic acid. And polyimide precursor, polyimide, polyamide and the like obtained. Furthermore, polymers other than a polyimide precursor, polyimide, and polyamide, specifically, an acrylic polymer, a methacrylic polymer, or polystyrene are also included.

  In the liquid crystal aligning agent of the present invention, at least one selected from polyimide precursors such as the polyamic acid and polyamic acid ester of the present invention, polyimide and polyamide, and the content of other polymers to be mixed as required are The total amount of the polymer components is preferably 1% by mass to 20% by mass, more preferably 3% by mass to 15% by mass, and particularly preferably 3% by mass to 10% by mass.

  The solvent which the liquid crystal aligning agent of this invention contains will not be specifically limited if it is an organic solvent which dissolves polymer components, such as a polyimide precursor of this invention, a polyimide, and polyamide. Specific examples thereof include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone, N-ethylpyrrolidone, N-vinylpyrrolidone, dimethyl sulfoxide, tetra Methylurea, pyridine, dimethylsulfone, hexamethylsulfoxide, γ-butyrolactone, 3-methoxy-N, N-dimethylpropanamide, 3-ethoxy-N, N-dimethylpropanamide, 3-butoxy-N, N-dimethylpropane Amide, 1,3-dimethyl-imidazolidinone, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, cyclohexanone, ethylene carbonate, propylene carbonate, diglyme, - such as hydroxy-4-methyl-2-pentanone and the like. These may be used alone or in combination.

  As long as the liquid crystal aligning agent of the present invention does not impair the effects of the present invention, an organic solvent (also called a poor solvent) that improves the uniformity and surface smoothness of the polymer film when the liquid crystal aligning agent is applied, or A compound may be contained. Furthermore, you may contain the compound etc. which improve the adhesiveness of a liquid crystal aligning film and a board | substrate.

  Specific examples of poor solvents that improve film thickness uniformity and surface smoothness include isopropyl alcohol, methoxymethylpentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol Tolu, ethyl carbitol acetate, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl Ether, diethylene glycol, diethylene glycol monoacetate , Diethylene glycol dimethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl Ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclo Hexene, propyl ether, dihexyl ether, n-to Sun, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, 3-methoxypropionic acid Methyl, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, 1-methoxy-2-propanol 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2- Acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2- (2-ethoxypropoxy) propanol, lactate methyl ester, lactate ethyl ester, lactate n-propyl ester, lactate n-butyl ester or lactic acid Examples thereof include organic solvents having a low surface tension such as isoamyl ester.

  These poor solvents may be used alone or in combination. When using the above solvent, it is preferable that it is 5-80 mass% of the whole solvent contained in a liquid crystal aligning agent, More preferably, it is 20-60 mass%.

  Examples of compounds that improve film thickness uniformity and surface smoothness include fluorine-based surfactants, silicone-based surfactants, and nonionic surfactants. More specifically, for example, F-top EF301, EF303, EF352 (manufactured by Tochem Products), MegaFuck F171, F173, R-30 (manufactured by Dainippon Ink), Florard FC430, FC431 (manufactured by Sumitomo 3M), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass) and the like. The use ratio of these surfactants is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass with respect to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent. .

  Examples of the compound that improves the adhesion between the liquid crystal alignment film and the substrate include a functional silane-containing compound and an epoxy group-containing compound, such as 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2- Aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3- Ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-To Methoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, ethylene glycol diglycidyl ether Polyethylene glycol Rudiglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromo Neopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N, N ′, N ′,-tetraglycidyl-m-xylenediamine, 1,3-bis ( N, N-diglycidylaminomethyl) cyclohexane or N, N, N ′, N ′,-tetraglycidyl-4,4′-diaminodiphenylmethane.

  When using the compound which improves adhesiveness with a board | substrate, it is preferable that the usage-amount is 0.1-30 mass parts with respect to 100 mass parts of polymer components contained in a liquid crystal aligning agent, More preferably. Is 1-20 parts by mass. If the amount used is less than 0.1 parts by mass, the effect of improving the adhesion cannot be expected, and if it exceeds 30 parts by mass, the orientation of the liquid crystal may deteriorate.

  In addition to the above, the liquid crystal aligning agent of the present invention has a dielectric or conductive material for the purpose of changing the electrical properties such as the dielectric constant and conductivity of the liquid crystal aligning film, as long as the effects of the present invention are not impaired. Further, a crosslinkable compound for the purpose of increasing the hardness and density of the liquid crystal alignment film may be added.

  The liquid crystal aligning agent of the present invention can be used as a liquid crystal aligning film after being applied and baked on a substrate and then subjected to alignment treatment by rubbing treatment or light irradiation (radiation irradiation) as necessary. Such a liquid crystal alignment film of the present invention is formed of a polyimide precursor, polyimide, or polyamide using the diamine represented by the above formula (1) as a raw material, so that the liquid crystal alignment performance by AC driving is difficult to change. is there.

  The substrate is not particularly limited as long as it is a highly transparent substrate. In addition to a glass substrate, a plastic substrate such as an acrylic substrate or a polycarbonate substrate can also be used. From the viewpoint of simplifying the process, it is preferable to use a substrate on which an ITO (Indium Tin Oxide) electrode for driving a liquid crystal is formed. In the reflective liquid crystal display element, an opaque substrate such as a silicon wafer can be used if only one substrate is used, and a material that reflects light such as aluminum can be used as an electrode in this case. As a high-performance element such as a TFT type element, an element in which an element such as a transistor is formed between an electrode for driving a liquid crystal and a substrate is used.

  A method for applying the liquid crystal aligning agent is not particularly limited, but industrially, a method of performing screen printing, offset printing, flexographic printing, an inkjet method, or the like is common. Other coating methods include a dipping method, a roll coater method, a slit coater method, a spinner method, and a spray method, and these may be used depending on the purpose.

  After the liquid crystal aligning agent is applied on the substrate, the liquid crystal alignment is performed by evaporating the solvent at 50 to 300 ° C., preferably 80 to 250 ° C., by a heating means such as a hot plate, a thermal circulation oven or an IR (infrared) oven. A film (polymer film) can be formed. If the thickness of the liquid crystal alignment film after baking is too thick, it is disadvantageous in terms of power consumption of the liquid crystal display element, and if it is too thin, the reliability of the liquid crystal display element may be lowered. Is 10 to 100 nm. When the liquid crystal is aligned horizontally or tilted, the liquid crystal can be aligned by treating the baked liquid crystal alignment film with rubbing or irradiation with polarized ultraviolet rays. For example, by irradiating light such as polarized ultraviolet rays, the photoreactive group derived from the diamine represented by the formula (1) undergoes a dimerization reaction, and the liquid crystal can be aligned with the anisotropy generated thereby.

  The liquid crystal display element of the present invention is a liquid crystal display element obtained by obtaining a substrate with a liquid crystal alignment film from the liquid crystal aligning agent of the present invention by the method described above, and then preparing a liquid crystal cell by a known method. For example, the two substrates disposed so as to face each other, the liquid crystal layer provided between the substrates, and the liquid crystal aligning agent of the present invention provided between the substrate and the liquid crystal layer. A liquid crystal display device comprising a liquid crystal cell having a liquid crystal alignment film. As such a liquid crystal display element of the present invention, a horizontal alignment (IPS: In-Plane Switching) system, a twisted nematic (TN) system, an OCB alignment (OCB: Optically Compensated Bend), a vertical alignment (VA: There are various types such as a vertical alignment method. Note that the liquid crystal alignment film only needs to be provided on at least one of the two substrates.

  The substrate used in the liquid crystal display element of the present invention is not particularly limited as long as it is a highly transparent substrate, but is usually a substrate on which a transparent electrode for driving liquid crystal is formed. As a specific example, the thing similar to the board | substrate described with the said liquid crystal aligning film can be mentioned.

  Further, the liquid crystal alignment film is formed by applying the liquid crystal aligning agent of the present invention on this substrate and baking it, and irradiating with radiation such as rubbing treatment or polarized ultraviolet rays as necessary. As described above.

  The liquid crystal material constituting the liquid crystal layer of the liquid crystal display element of the present invention is not particularly limited, and a positive liquid crystal having positive dielectric anisotropy or a negative liquid crystal having negative dielectric anisotropy can be used. As a specific example, a liquid crystal material used in a conventional horizontal alignment method, for example, MLC-2041 manufactured by Merck Ltd. can be used.

  For example, a pair of substrates on which a liquid crystal alignment film is formed is prepared, spacers such as beads are dispersed on the liquid crystal alignment film of one substrate, and the liquid crystal alignment film surface is on the inside. In this way, the other substrate is bonded and the liquid crystal is injected under reduced pressure to seal, or the liquid crystal is dropped on the liquid crystal alignment film surface on which the spacers are dispersed and then the substrate is bonded and sealed. Can be illustrated. The thickness of the spacer at this time is preferably 1 to 30 μm, more preferably 2 to 10 μm. In the case of a horizontal alignment type liquid crystal display element, after the liquid crystal is sealed in this way, a polarizing plate is disposed outside the substrate.

  As described above, the liquid crystal display device manufactured using the liquid crystal aligning agent of the present invention has a liquid crystal alignment film in which the change in the liquid crystal alignment performance due to AC driving is suppressed, and thus has excellent afterimage characteristics and image sticking. Thus, the liquid crystal display element is less likely to cause display defects and contrast deterioration.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to the examples.
The abbreviations used in this example are as follows.
CBDA: 1,2,3,4-cyclobutanetetracarboxylic dianhydride BODA: bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic dianhydride NMP: N-methyl-2 -Pyrrolidone BCS: Butyl cellosolv DA-1: Diamine represented by the following formula

下記式で表されるジアミン［１］〜［７］

Diamines represented by the following formulas [1] to [7]

下記式で表されるジアミン［８］〜［１２］

Diamines represented by the following formulas [8] to [12]

<Measurement of ¹ H-NMR>
The measurement conditions of ¹ H-NMR in the synthesis examples are as follows.
Apparatus: Fourier transform type superconducting nuclear magnetic resonance apparatus (FT-NMR) INOVA-400 (manufactured by Varian) 400 MHz
Solvent: deuterated dimethyl sulfoxide (DMSO-d ₆ ), deuterated chloroform (CDCl ₃ )
Standard substance: Tetramethylsilane (TMS)

<Polymer molecular weight measurement>
Moreover, the molecular weight measurement conditions of a polymer (polyamic acid etc.) are as follows.
Apparatus: Room temperature gel permeation chromatography (GPC) apparatus (SSC-7200) manufactured by Senshu Scientific Co., Ltd.
Column: Column made by Shodex (KD-803, KD-805)
Column temperature: 50 ° C
Eluent: N, N′-dimethylformamide (as additives, lithium bromide-hydrate (LiBr · H ₂ O) is 30 mmol / L, phosphoric acid / anhydrous crystal (o-phosphoric acid) is 30 mmol / L, Tetrahydrofuran (THF) 10ml / L)
Flow rate: 1.0 ml / min. Standard sample for preparing a calibration curve: TSK standard polyethylene oxide (molecular weight of about 900,000, 150,000, 100,000, 30,000) manufactured by Tosoh Corporation, and polyethylene glycol (manufactured by Polymer Laboratories) Molecular weight about 12,000, 4,000, 1,000).

<Synthesis of diamine>
Synthesis Example 1 Synthesis of Diamine [1] ((E, E) -Bis- (4′-aminophenyl) 1,4-benzenediacrylate)

To a 2 L four-necked flask, terephthalaldehyde [A] (40.00 g, 298 mmol), pyridine (46 g) and piperidine (7.0 g) were added, and the reaction solution was heated to 100 ° C. with stirring. A pyridine solution (500 g) of malonic acid [B] (140.0 g, 1.34 mol) was added dropwise thereto. After confirming the completion of the reaction by HPLC (high performance liquid chromatography), the reaction solution was cooled to 40 ° C., and the reaction solution was poured into distilled water (1 L). Subsequently, concentrated hydrochloric acid was added until the reaction solution became acidic, and then the solid was filtered, washed with water, washed with methanol, and dried under reduced pressure to obtain Compound [C] (yield: 60.3 g, yield: 93%). The ¹ H-NMR measurement result of the obtained compound [C] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 12.4 (2H, brs), 7.74 (4H, s), 7.60 (2H, d), 6.61 (2H, d).

Next, in a 1 L four-necked flask, compound [C] (30.00 g, 138 mmol), 4-nitrophenol [D] (42.08 g, 303 mmol), 1-ethyl-3- (3-dimethylaminopropyl) Carbodiimide hydrochloride (hereinafter abbreviated as EDC) (68.53 g, 358 mmol), 4-N, N-dimethylaminopyridine (hereinafter abbreviated as DMAP) (3.56 g, 27.5 mmol), tetrahydrofuran (hereinafter referred to as THF) (Omitted) (600 g) was added and stirred at 23 ° C. After confirming the completion of the reaction by HPLC, the reaction solution is poured into a mixed solution of ethyl acetate (500 mL) / distilled water (1 L), and the solid is filtered, washed with a mixed solution of ethyl acetate / methanol 1: 1, and dried under reduced pressure. [E] was obtained (yield: 60.6 g, yield: 96%). The ¹ H-NMR measurement result of the obtained compound [E] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 8.36-8.31 (4H, m), 7.92 (2H, d), 7.68 (4H, s), 7.40-7.37 (4H, m), 6.70 (2H , d).

Next, compound [E] (63.30 g, 138 mmol), tin chloride (182.5 g, 962 mmol), THF (630 g) and distilled water (440 g) are added to a 2 L four-necked flask, and the mixture is heated and stirred at 70 ° C. Went. After confirming the completion of the reaction by HPLC, N, N-dimethylacetamide (1 L) was added, and the reaction solution was diluted with ethyl acetate (2.5 L), and carbonic acid was added until no by-product tin hydroxide was precipitated. Sodium hydride was added. Thereafter, the supernatant was filtered, the filtrate was separated, and the aqueous layer was removed. Thereafter, the organic layer was washed successively with 1 L of saturated aqueous sodium hydrogen carbonate solution (twice) and brine (twice), and the organic layer was dried over magnesium sulfate. After filtration, the solvent was distilled off with an evaporator to obtain a crude product, methanol (200 mL) was added, the mixture was stirred at room temperature (23 ° C.) for 30 minutes, filtered again, washed with methanol, dried under reduced pressure, and diamine. [1] was obtained (yield: 24.0 g, yield: 44%). The ¹ H-NMR measurement result of the obtained diamine [1] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 7.83 (4H, s), 7.79 (2H, d), 6.89 (2H, d), 6.81-6.78 (4H, m), 6.56-6.53 (4H , m), 5.04 (4H, brs).

  Synthesis Example 2 Synthesis of Diamine [2] ((E, E) -Bis- (4′-aminophenylethyl) 1,4-benzenediacrylate)

  In a 1 L four-necked flask, compound [C] (30.21 g, 138 mmol), 2- (4-nitrophenyl) ethanol [F] (50.91 g, 305 mmol), EDC (68.98 g, 360 mmol), DMAP ( 3.38 g, 27.9 mmol) and THF (600 g) were added, and the mixture was stirred at 23 ° C. After confirming the completion of the reaction by HPLC, the reaction solution was poured into a mixed solution of ethyl acetate (1 L) / distilled water (1 L), the solid was filtered, washed with a mixed solution of ethyl acetate / methanol 1: 1, and dried under reduced pressure to give a compound. [G] was obtained (yield: 70.9 g, yield: 99%).

Next, compound [G] (71.48 g, 138 mmol), tin chloride (183.4 g, 969 mmol), THF (715 g), and distilled water (500 g) are added to a 2 L four-necked flask, and the mixture is heated and stirred at 70 ° C. Went. After confirming the completion of the reaction by HPLC, N, N-dimethylacetamide (1 L) was added, and the reaction solution was diluted with ethyl acetate (2.5 L), and carbonic acid was added until no by-product tin hydroxide was precipitated. Sodium hydride was added. Thereafter, the supernatant was filtered, the filtrate was separated, and the aqueous layer was removed. Thereafter, the organic layer was washed successively with 1 L of saturated aqueous sodium hydrogen carbonate solution (twice) and brine (twice), and the organic layer was dried over magnesium sulfate. After filtration, the solvent was distilled off with an evaporator to obtain a crude product, methanol (200 mL) was added, the mixture was stirred at room temperature for 30 minutes, filtered, washed with methanol, dried under reduced pressure, and diamine [2] was added. Obtained (yield: 30.6 g, yield: 48%). The ¹ H-NMR measurement result of the obtained diamine [2] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 7.66 (2H, d), 7.73 (4H, s), 7.60 (2H, d), 6.90-6.88 (4H, m), 6.66 (2H, d ), 6.45-6.46 (4H, m), 4.88 (4H, brs), 4.21 (4H, t), 2.75 (4H, t).

  Synthesis Example 3 Synthesis of Diamine [3] ((E, E) -Bis- (4′-aminophenyl) 1,3-benzenediacrylate)

Isophthalaldehyde [H] (50.00 g, 373 mol), pyridine (78 g), and piperidine (9.5 g) were added to a 2 L four-necked flask, and the reaction solution was heated to 100 ° C. with stirring. A pyridine solution (600 g) of malonic acid [B] (169.5 g, 1.68 mol) was added dropwise thereto. After confirming the completion of the reaction by HPLC, the reaction solution was cooled to 40 ° C., and the reaction solution was poured into distilled water (1 L). Next, concentrated hydrochloric acid was added until the reaction solution became acidic, and then the solid was filtered and washed with water to obtain a crude product of compound [I]. The crude product was stirred with an ethyl acetate / methanol 1: 1 mixed solution at room temperature for 30 minutes, filtered, washed with ethyl acetate, and then dried under reduced pressure to obtain Compound [I] (yield: 80.2 g, Yield: 99%). The ¹ H-NMR measurement results of the obtained compound [I] are shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 12.4 (2H, brs), 8.07 (1H, s), 7.72 (2H, dd), 7.61 (2H, d), 7.46 (1H, t).

Next, in a 1 L four-necked flask, compound [I] (30.00 g, 138 mmol), 4-nitrophenol [D] (40.17 g, 289 mmol), EDC (63.26 g, 330 mmol), DMAP (3. 36 g, 27.5 mmol) and THF (600 g) were added, and the mixture was stirred at 23 ° C. After confirming the completion of the reaction by HPLC, the reaction solution was poured into a mixed solution of ethyl acetate (500 mL) / distilled water (1 L), the solid was filtered, washed with ethyl acetate, and dried under reduced pressure to obtain compound [J] ( (Yield: 62.1 g, yield: 98%). The ¹ H-NMR measurement result of the obtained compound [J] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 8.37 (1H, s), 8.32-8.29 (4H, m), 7.92 (2H, d), 7.88 (2H, dd), 7.56-7.51 (5H m), 7.08 (2H, d).

Next, compound [J] (62.1 g, 135 mmol), tin chloride (182.5 g, 962 mmol), THF (630 g) and distilled water (630 g) were added to a 2 L four-necked flask, and the mixture was heated and stirred at 70 ° C. Went. After confirming the completion of the reaction by HPLC, the reaction solution was diluted with ethyl acetate (2 L), and sodium bicarbonate was added until no by-product tin hydroxide was precipitated. Thereafter, the supernatant was filtered, the filtrate was separated, and the aqueous layer was removed. Thereafter, the organic layer was washed successively with 1 L of saturated aqueous sodium hydrogen carbonate solution (twice) and brine (twice), and the organic layer was dried over magnesium sulfate. After filtration, the solvent was distilled off with an evaporator to obtain a crude product, methanol (200 mL) was added, the mixture was stirred at room temperature for 30 minutes, filtered, washed with methanol, and dried under reduced pressure to obtain diamine [3 (Yield: 34.1 g, Yield: 54%). The ¹ H-NMR measurement result of the obtained diamine [3] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 8.27 (1H, s), 7.82-7.77 (4H, m), 7.49 (1H, t), 6.96 (2H, d), 6.82-6.78 (4H , m), 6.56-6.53 (4H, m), 5.04 (4H, brs).

  Synthesis Example 4 Synthesis of Diamine [4] ((E, E) -Bis- (4′-aminophenylethyl) 1,3-benzenediacrylate)

In a 1 L four-necked flask, compound [I] (54.92 g, 252 mmol), 2- (4-nitrophenyl) ethanol [F] (92.58 g, 554 mmol), EDC (125.4 g, 654 mmol), DMAP ( 6.15 g, 50.3 mmol) and THF (1.1 Kg) were added, and the mixture was stirred at 23 ° C. After confirming the completion of the reaction by HPLC, ethyl acetate (1 L) / hexane (500 mL) / distilled water (1 L) was added to the reaction solution, and the aqueous layer was removed by a liquid separation operation. Thereafter, the organic layer was washed three times with brine (1 L), and the organic layer was dried over magnesium sulfate. After filtration, the solvent was distilled off with an evaporator to obtain a crude product of compound [K]. Methanol (300 g) was added to this crude product and stirred at room temperature for 30 minutes, followed by filtration and drying under reduced pressure to obtain compound [K] (yield: 82.2 g, yield: 63%). The ¹ H-NMR measurement result of the obtained compound [K] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 8.17-8.14 (4H, m), 8.11 (1H, s), 7.70 (2H, dd), 7.62 (1H, s), 7.59-7.56 (5H , m), 7.42 (1H, t), 6.71 (2H, d), 4.41 (4H, t), 3.10 (4H, t).

Next, compound [K] (82.21 g, 139 mmol), tin chloride (211.3 g, 1.11 mol), THF (820 g), and distilled water (820 g) were added to a 2 L four-necked flask at 70 ° C. Heating and stirring were performed. After confirming the completion of the reaction by HPLC, the reaction solution was diluted with ethyl acetate (2.5 L), and sodium bicarbonate was added until no by-product tin hydroxide was precipitated. Thereafter, the supernatant was filtered, the filtrate was separated, and the aqueous layer was removed. Thereafter, the organic layer was washed successively with 1 L of saturated aqueous sodium hydrogen carbonate solution (twice) and brine (twice), and the organic layer was dried over magnesium sulfate. After filtration, the solvent was distilled off with an evaporator to obtain a crude product, methanol (200 mL) was added, and the mixture was stirred at room temperature for 30 minutes, then filtered, washed with methanol, and dried under reduced pressure to give diamine [4 (Yield: 46.1 g, Yield: 73%). The ¹ H-NMR measurement result of the obtained diamine [4] is shown below.
¹ H-NMR (400 MHz, CDCl3, δ ppm): 7.66 (2H, d), 7.63 (1H, s), 7.54-7.39 (1H, m), 7.07-7.04 (4H, m), 6.68-6.65 (4H, m), 6.45 (2H, d), 5.04 (4H, brs), 4.37 (4H, t), 2.91 (4H, t).

  Synthesis Example 5 Synthesis of diamine [5] ((E) -4-aminophenethyl 3- (4-aminophenyl) acrylate)

  In a 500 mL reaction vessel, compound [M] (12.7 g, 65.8 mmol), 2- (4-nitrophenyl) ethanol [F] (10 g, 59.8 mmol), EDC (15 g, 77.7 mmol), DMAP ( 365 mg, 3 mmol) and 200 g of THF were added, and the atmosphere was replaced with nitrogen, followed by stirring at room temperature. After completion of the reaction, the reaction solution was poured into distilled water (2 L), and the obtained crystals were suspended in isopropyl alcohol (100 g) to obtain compound [N] (yield: 18.4 g, yield: 90). %).

To a 500 mL reaction vessel, add the compound [N] obtained above (22.4 g, 65.5 mmol), tin chloride (II) (80 g, 458.7 mmol), THF 200 g, and distilled water 100 g at 60 ° C. Stir with heating. After completion of the reaction, the reaction solution was neutralized with sodium hydrogen carbonate and extracted with ethyl acetate. After the solvent was distilled off, the yellow crystals were dried to obtain diamine [5] (yield: 14.0 g, yield: 76%). The ¹ H-NMR measurement result of the obtained diamine [5] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 7.46 (1H, d), 7.37 (2H, d), 6.92 (2H, d), 6.56-6.47 (4H, m), 6.20 (1H, d ), 5.78 (2H, s), 4.89 (2H, s), 4.18 (2H, t), 2.74 (2H, t).

  Synthesis Example 6 Synthesis of Diamine [6] ((2E, 2'E) -pentane-1,5-diyl bis (3- (4-aminophenyl) acrylate))

  In a 500 mL reaction vessel, compound [M] (37.5 g, 160.2 mmol), compound [O] (6.4 g, 61.6 mmol), EDC (41.6 g, 172.5 mmol), DMAP (828 mg, 6. 8 mmol) and 300 g of THF were added and stirred at room temperature. After completion of the reaction, the reaction solution was poured into distilled water (2 L) to obtain crystals. The precipitated crystals were dried under reduced pressure to obtain compound [P] (30 g).

Add the compound [P] obtained above (15 g, 33.0 mmol), tin (II) chloride (43.8 g, 231.0 mmol), THF 150 g, and distilled water 150 g to a 500 mL reaction vessel and heat at 60 ° C. Stir. After completion of the reaction, the reaction solution was neutralized with sodium hydrogen carbonate and extracted with ethyl acetate. After the solvent was distilled off, the yellow crystals were suspended and washed with ethyl acetate and hexane to obtain diamine [6] (yield: 11.9 g, yield: 91%). The ¹ H-NMR measurement result of the obtained diamine [6] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 7.47 (2H, d), 7.36 (4H, d), 6.55 (4H, d), 6.22 (2H, d), 5.76 (4H, s), 4.10 (4H, t), 1.99-1.63 (4H, m), 1.46-1.40 (2H, m).

  Synthesis Example 7 Synthesis of diamine [7] ((E) -4-aminophenyl 3- (4-aminophenyl) acrylate)

  In a 500 mL reaction vessel, compound [M] (34 g, 193.2 mmol), 4-nitrophenol [D] (25.0 g, 179.7 mmol), EDC (40.4 g, 191.7 mmol), DMAP (2.2 g) 18 mmol) and 300 g of THF were added and stirred at room temperature. After completion of the reaction, the reaction solution was poured into distilled water (3 L), and the precipitated white crystals were separated by filtration. The obtained crude crystal was suspended and washed with isopropyl alcohol (200 g) to obtain compound [Q] (52 g, 165.7 mmol).

In a 2 L reaction vessel, the compound [Q] obtained above (30 g, 95.5 mmol), reduced iron (21.0 g, 382 mmol), ammonium chloride (40.8 g, 762.8 mmol), N, N- 200 g of dimethylformaldehyde, 200 g of ethyl acetate and 400 g of distilled water were added, and the mixture was heated and stirred at 70 ° C. After completion of the reaction, the mixture was extracted with ethyl acetate, treated with activated carbon, and the solvent was distilled off to obtain crude crystals. The resulting crude crystals were purified by suspension washing with methanol and hexane to obtain diamine [7] (yield: 19.4 g, yield: 80%). The ¹ H-NMR measurement result of the obtained diamine [7] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 7.60 (1H, d), 7.43 (2H, d), 6.78 (2H, d), 6.77-6.36 (4H, m), 6.10 (1H, d ), 5.85 (2H, s), 5.02 (2H, s).

  Synthesis Example 8 Synthesis of Diamine [8] ((E, E) -Bis- (3′-aminophenyl) 1,3-benzenediacrylate)

In a 2 L four-necked flask, compound [I] (40.00 g, 183 mmol), 3-nitrophenol [R] (53.56 g, 385 mmol), EDC (84.33 g, 440 mmol), DMAP (4.48 g, 36 0.7 mmol) and THF (800 g) were added, and the mixture was stirred at 23 ° C. After confirming the completion of the reaction by HPLC, the reaction solution is poured into an ethyl acetate (100 mL) / distilled water (1 L) solution, and the solid is filtered, washed sequentially with distilled water, ethyl acetate, and a THF / hexane mixed solvent, and dried under reduced pressure. Yielded compound [S] (83.5 g, 99% yield). The ¹ H-NMR measurement result of the obtained compound [S] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 8.37 (1H, s), 8.15-8.13 (4H, m), 7.94-7.87 (4H, m), 7.74-7.72 (4H, m), 7.54 (1H, t), 7.07 (2H, d).

Next, in a 2 L four-necked flask, compound [S] (83.5 g, 181 mmol), iron powder (61.4 g, 1.1 mol), ammonium chloride (29.4 g, 550 mmol), ethyl acetate (760 g), DMF (500 g) and distilled water (260 g) were added, and the mixture was heated and stirred at 70 ° C. After confirming the completion of the reaction by HPLC, celite filtration was performed, and ethyl acetate (1 L) was added to the filtrate for liquid separation. The organic layer was washed 3 times with saturated brine (1 L), and the organic layer was dried over magnesium sulfate. After filtration, the solvent was distilled off with an evaporator and dried under reduced pressure to obtain diamine [8] (48.2 g, yield 66%). The ¹ H-NMR measurement result of the obtained diamine [8] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 8.32 (1H, s), 7.83-7.79 (4H, m), 7.50 (1H, t), 7.03-6.97 (4H, m), 6.44-6.41 (2H, m), 6.33-6.32 (2H, m), 6.28-6.25 (2H, m), 5.27 (4H, brs).

  Synthesis Example 9 Synthesis of diamine [9] ((E) -3-aminophenyl 3- (4-aminophenyl) acrylate)

The starting material was changed to 3-nitrophenol [R], and the same operation as in Synthesis Example 7 was performed to obtain diamine [9] (yield: 38 g, yield: 85%). The ¹ H-NMR measurement result of the obtained diamine [9] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 7.62 (1H, d), 7.45 (2H, d), 7.01 (1H, t), 6.58 (1H, d), 6.44 (1H, s), 6.42 (1H, d), 6.31 (1H, d), 6.25 (1H, d), 5.86 (2H, s), 5.25 (2H, s)

  Synthesis Example 10 Synthesis of Diamine [10] ((E) -3-aminophenyl 3- (3-aminophenyl) acrylate)

The starting material was changed to compound [S] and 3-nitrophenol [R], and the same operation as in Synthesis Example 7 was performed to obtain dinitro compound [T]. The obtained dinitro compound [T] was used as a starting compound, and the same operation as in Synthesis Example 7 was performed to obtain diamine [10] (yield: 22 g). The ¹ H-NMR measurement result of the obtained diamine [10] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 7.60 (1H, d), 7.10 (1H, t), 6.90 (1H, d), 6.88 (1H, s), 6.83 (2H, dt), 6.68 (1H, d), 6.63 (1H, d), 6.59 (2H, dt), 5.23 (2H, s), 5.06 (2H, s)

  Synthesis Example 11 Synthesis of Diamine [11] ((E) -4-aminophenyl 3- (3-aminophenyl) acrylate)

The starting material was changed to compound [S] and 4-nitrophenol [D], and the same operation as in Synthesis Example 7 was performed to obtain dinitro compound [U]. Using the obtained compound [U] as a starting compound, the same operation as in Synthesis Example 7 was performed to obtain diamine [11] (yield: 22 g). The ¹ H-NMR measurement result of the obtained diamine [11] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 7.64 (1H, d), 7.10 (1H, t), 7.04 (1H, t), 6.92-6.88 (2H, m), 6.67 (1H, d ), 6.60 (1H, d), 6.46 (1H, d), 6.44-6.34 (1H, m), 6.30-6.27 (1H, m), 5.25 (2H, s), 5.23 (2H, s)

  Synthesis Example 12 Synthesis of Diamine [12] ((2E, 2'E) -ethane-1,2-diyl bis (3- (4-aminophenyl) acrylate))

The starting material was changed to compound [M] and ethylene glycol [V], and the same operation as in Synthesis Example 6 was performed to obtain dinitro compound [W]. The obtained dinitro compound [W] was used as a starting compound, and the same operation as in Synthesis Example 6 was performed to obtain diamine [12] (yield: 10.2 g). The ¹ H-NMR measurement result of the obtained diamine [12] is shown below.
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm) 8.25-8.23 (4H, d), 8.05-8.02 (4H, d), 7.80 (2H, d), 6.92 (2H, d), 5.76 (4H, s), 4.40 (4H, s)

(Comparative Synthesis Example 1) Synthesis of Diamine D-1 Diamine DA-1 was synthesized according to Example 1 of JP-T-2001-517719.

<Preparation of liquid crystal aligning agent>
(Preparation of liquid crystal aligning agent A1)
NMP (5.0 g) was added to diamine [1] (1.20 g, 3.0 mmol), and after stirring at room temperature for complete dissolution, CBDA (0.53 g, 2.8 mmol) and NMP (5. 0 g) was added and reacted at room temperature for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A1. The number average molecular weight of this polyamic acid was 6000, and the weight average molecular weight was 10,500.

(Preparation of liquid crystal aligning agent A2)
NMP (5.4 g) was added to diamine [2] (1.37 g, 3.0 mmol), and after stirring at room temperature for complete dissolution, CBDA (0.55 g, 2.8 mmol) and NMP (5. 4 g) was added and reacted at room temperature for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A2. The number average molecular weight of this polyamic acid was 3800, and the weight average molecular weight was 5000.

(Preparation of liquid crystal aligning agent A3)
NMP (5.0 g) was added to diamine [3] (1.20 g, 3.0 mmol), and after stirring at room temperature for complete dissolution, CBDA (0.55 g, 2.8 mmol) and NMP (5. 0 g) was added and reacted at room temperature for 10 hours to obtain a polyamic acid solution. NMP (10.0 g) and BCS (5.0 g) were added to this polyamic acid solution (10 g), and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent A3. The number average molecular weight of this polyamic acid was 8100, and the weight average molecular weight was 16000.

(Preparation of liquid crystal aligning agent A4)
NMP (5.4 g) was added to diamine [4] (1.37 g, 3.0 mmol), and after stirring at room temperature for complete dissolution, CBDA (0.55 g, 2.8 mmol) and NMP (5. 4 g) was added and reacted at room temperature for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A4. The number average molecular weight of this polyamic acid was 5200, and the weight average molecular weight was 7600.

(Preparation of liquid crystal aligning agent A5)
NMP (32.3 g) was added to diamine [5] (7.06 g, 25.0 mmol), and the mixture was stirred at room temperature for complete dissolution, and then CBDA (4.51 g, 23.0 mmol) and NMP (33. 2 g) was added and reacted at room temperature for 10 hours to obtain a polyamic acid solution. NMP (40.0g) and BCS (20.0g) were added to this polyamic acid solution (40g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A5. The number average molecular weight of this polyamic acid was 10500, and the weight average molecular weight was 57000.

(Preparation of liquid crystal aligning agent A6)
NMP (4.9 g) was added to diamine [6] (1.18 g, 3.0 mmol), and after stirring at room temperature for complete dissolution, CBDA (0.53 g, 2.7 mmol) and NMP (4. 9 g) was added and reacted at room temperature for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A6. The number average molecular weight of this polyamic acid was 8800, and the weight average molecular weight was 35000.

(Preparation of liquid crystal aligning agent A7)
NMP (5.6 g) was added to diamine [7] (1.14 g, 4.5 mmol) and stirred at room temperature for complete dissolution, and then CBDA (0.83 g, 4.2 mmol) and NMP (5. 6 g) was added and reacted at room temperature for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A7. The number average molecular weight of this polyamic acid was 13800, and the weight average molecular weight was 35500.

(Preparation of liquid crystal aligning agent A8)
NMP (33.3 g) was added to diamine [8] (4.00 g, 10.0 mmol), stirred at room temperature for complete dissolution, and then CBDA (1.86 g, 9.5 mmol) was added at room temperature. The mixture was reacted for 10 hours to obtain a polyamic acid solution. NMP (10.0 g) and BCS (5.0 g) were added to this polyamic acid solution (10 g), and the mixture was stirred at room temperature for 5 hours to obtain liquid crystal aligning agent A8. The number average molecular weight of this polyamic acid was 8000, and the weight average molecular weight was 21,200.

(Preparation of liquid crystal aligning agent A9)
NMP (24.6 g) was added to diamine [9] (2.54 g, 10.0 mmol), stirred at room temperature to dissolve completely, and then CBDA (1.80 g, 9.2 mmol) was added at room temperature. The mixture was reacted for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A9. The number average molecular weight of this polyamic acid was 15900, and the weight average molecular weight was 43400.

(Preparation of liquid crystal aligning agent A10)
After adding NMP (25.0 g) to diamine [10] (2.54 g, 10.0 mmol) and stirring at room temperature to completely dissolve, CBDA (1.86 g, 9.5 mmol) was added and at room temperature. The mixture was reacted for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A10. The number average molecular weight of this polyamic acid was 4300, and the weight average molecular weight was 7800.

(Preparation of liquid crystal aligning agent A11)
NMP (25.0 g) was added to diamine [11] (2.54 g, 10.0 mmol), stirred at room temperature for complete dissolution, and then CBDA (1.86 g, 9.5 mmol) was added at room temperature. The mixture was reacted for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A11. The number average molecular weight of this polyamic acid was 7600, and the weight average molecular weight was 18,600.

(Preparation of liquid crystal aligning agent A12)
After adding NMP (30.5 g) to diamine [12] (3.52 g, 10.0 mmol) and stirring at room temperature to completely dissolve, CBDA (1.86 g, 9.5 mmol) was added, and at room temperature. The mixture was reacted for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A12. The number average molecular weight of this polyamic acid was 12100, and the weight average molecular weight was 32300.

(Preparation of liquid crystal aligning agent A13)
NMP (13.9 g) was added to diamine [9] (2.54 g, 10.0 mmol), and after stirring at room temperature for complete dissolution, BODA (2.38 g, 9.5 mmol) and NMP (13. 9 g) was added and reacted at 80 ° C. for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A13. The number average molecular weight of this polyamic acid was 6200, and the weight average molecular weight was 14900.

(Preparation of liquid crystal aligning agent A14)
NMP (14.2 g) was added to diamine [10] (2.54 g, 10.0 mmol), and after stirring at room temperature for complete dissolution, BODA (2.45 g, 9.8 mmol) and NMP (14. 2 g) was added and reacted at 80 ° C. for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A14. The number average molecular weight of this polyamic acid was 4200, and the weight average molecular weight was 8,000.

(Preparation of liquid crystal aligning agent A15)
NMP (14.2 g) was added to diamine [11] (2.54 g, 10.0 mmol) and stirred at room temperature for complete dissolution, and then BODA (2.45 g, 9.8 mmol) and NMP (14. 2 g) was added and reacted at 80 ° C. for 10 hours to obtain a polyamic acid solution. NMP (10.0g) and BCS (5.0g) were added to this polyamic acid solution (10g), and it stirred at room temperature for 5 hours, and obtained liquid crystal aligning agent A15. The number average molecular weight of this polyamic acid was 5700, and the weight average molecular weight was 12100.

(Preparation of liquid crystal aligning agent B1)
NMP (22.0 g) was added to DA-1 (5.10 g, 14.0 mmol), and the mixture was stirred and completely dissolved at room temperature. Then, CBDA (2.66 g, 13.6 mmol) and NMP (22.0 g) were added. ) And reacted at room temperature for 5 hours to obtain a polyamic acid solution. NMP (40.0 g) and BCS (20.0 g) were added to this polyamic acid solution (40 g), and the mixture was stirred at room temperature for 5 hours to obtain liquid crystal aligning agent B1. The number average molecular weight of this polyamic acid was 6500, and the weight average molecular weight was 26000.

<Production of liquid crystal cell>
(Example 1)
Using the liquid crystal aligning agent A1, a liquid crystal cell was produced according to the procedure shown below.
The substrate used was a glass substrate having a size of 30 mm × 40 mm and a thickness of 0.7 mm, on which comb-like pixel electrodes formed by patterning an ITO film were arranged. The pixel electrode has a comb-like shape configured by arranging a plurality of dog-shaped electrode elements whose central portion is bent. The width in the short direction of each electrode element is 3 μm, and the distance between the electrode elements is 6 μm. The pixel electrode forming each pixel is configured by arranging a plurality of dog-shaped electrode elements whose central part is bent, so that the shape of each pixel is not rectangular, and is similar to the electrode element in the central part. It has a shape that bends and resembles a bold-faced koji. Each pixel is divided into upper and lower portions with a central bent portion as a boundary, and has a first region on the upper side of the bent portion and a second region on the lower side. When the first region and the second region of each pixel are compared, the formation directions of the electrode elements of the pixel electrodes constituting them are different. That is, when the alignment processing direction of the liquid crystal alignment film described later is used as a reference, the electrode element of the pixel electrode is formed to form an angle of + 10 ° (clockwise) in the first region of the pixel, and in the second region of the pixel The electrode elements of the pixel electrode are formed so as to form an angle of −10 ° (counterclockwise). That is, in the first region and the second region of each pixel, the directions of the rotation operation (in-plane switching) of the liquid crystal induced by the voltage application between the pixel electrode and the counter electrode are mutually in the substrate plane. It is comprised so that it may become a reverse direction.

The liquid crystal aligning agent A1 was spin-coated on the prepared substrate with electrodes. Subsequently, after drying for 60 seconds with a 90 degreeC hotplate, it baked for 30 minutes with a 200 degreeC hot-air circulation type oven, and formed the liquid crystal aligning film with a film thickness of 100 nm. Next, the substrate was placed on a hot plate at 240 ° C., and the surface of the liquid crystal alignment film was irradiated with 313 nm ultraviolet rays at 20 mJ / cm ² via a polarizing plate to obtain a substrate with a liquid crystal alignment film. In addition, a liquid crystal alignment film was formed using a liquid crystal aligning agent A1 on a glass substrate having a columnar spacer with a height of 4 μm on which no electrode was formed as a counter substrate, and subjected to alignment treatment.

  A sealant (XN-1500T manufactured by Kyoritsu Chemical Co., Ltd.) was printed on the liquid crystal alignment film of one substrate. Next, the other substrate was bonded so that the liquid crystal alignment film faces each other and the alignment direction was 0 °, and then the sealing agent was cured to produce an empty cell. Liquid crystal MLC-2041 (manufactured by Merck & Co., Inc.) was injected into this empty cell by a reduced pressure injection method, the injection port was sealed, and a liquid crystal cell having a configuration of an IPS (In-Plane Switching) mode liquid crystal display element ( IPS mode liquid crystal cell) was obtained.

(Liquid crystal alignment performance evaluation)
The alignment state of the liquid crystal cell for IPS mode obtained above was observed with a polarizing microscope, and “good” was obtained when there was no alignment defect, and “bad” when there was an alignment defect. The results are shown in Table 1.

(Afterimage evaluation)
The IPS mode liquid crystal cell obtained above is placed between two polarizing plates arranged so that the polarization axes are orthogonal to each other, the light source is turned on with no voltage applied, and the transmitted light has the highest luminance. The arrangement angle of the liquid crystal cell was adjusted so as to be small. Then, the rotation angle (alignment azimuth angle) when the liquid crystal cell was rotated from the angle at which the second region of the pixel was darkest to the angle at which the first region was darkest was calculated as the initial alignment azimuth. Next, an AC voltage of 8 V _PP was applied for 24 hours at a frequency of 30 Hz in a room temperature environment. Thereafter, the pixel electrode and the counter electrode of the liquid crystal cell were short-circuited and left as it was at room temperature for 1 hour. After standing, the orientation azimuth is measured in the same manner, and the difference in orientation azimuth before and after AC driving, that is, the orientation azimuth before AC driving—the orientation azimuth after AC driving is expressed as Δ orientation azimuth (°). Calculated as The results are shown in Table 1.

(Example 2)
Except for using the liquid crystal aligning agent A2 instead of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to evaluate the liquid crystal alignment performance and the afterimage evaluation.

(Example 3)
Except for using the liquid crystal aligning agent A3 instead of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to evaluate the liquid crystal aligning performance and the afterimage.

Example 4
Except for using the liquid crystal aligning agent A4 instead of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to evaluate the liquid crystal aligning performance and the afterimage evaluation.

(Example 5)
Except for using the liquid crystal aligning agent A5 instead of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to perform the liquid crystal alignment performance evaluation and the afterimage evaluation.

(Example 6)
Except for using the liquid crystal aligning agent A7 instead of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to evaluate the liquid crystal aligning performance and the afterimage evaluation.

(Example 7)
Except for using the liquid crystal aligning agent A8 in place of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to evaluate the liquid crystal aligning performance and the afterimage.

(Example 8)
Except for using the liquid crystal aligning agent A9 in place of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to evaluate the liquid crystal alignment performance and the afterimage evaluation.

Example 9
Except for using the liquid crystal aligning agent A10 in place of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to evaluate the liquid crystal aligning performance and the afterimage.

(Example 10)
Except for using the liquid crystal aligning agent A11 in place of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to evaluate the liquid crystal aligning performance and the afterimage.

(Example 11)
Except for using the liquid crystal aligning agent A12 in place of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to evaluate the liquid crystal aligning performance and the afterimage.

(Example 12)
Except for using the liquid crystal aligning agent A13 in place of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed, and the liquid crystal alignment performance evaluation and the afterimage evaluation were performed.

(Example 13)
Except for using the liquid crystal aligning agent A14 in place of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed, and the liquid crystal alignment performance evaluation and the afterimage evaluation were performed.

(Example 14)
Except for using the liquid crystal aligning agent A15 in place of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to evaluate the liquid crystal aligning performance and the afterimage evaluation.

(Comparative Example 1)
Except for using the liquid crystal aligning agent B1 instead of the liquid crystal aligning agent A1, the same operations as in Example 1 were performed to evaluate the liquid crystal aligning performance and the afterimage.

  As a result, as shown in Table 1, the diamine represented by the above formula (1) is used as a raw material in the main chain skeleton of the polyimide polymer, regardless of the low temperature and short time measurement conditions of 24 hours at room temperature. It can be seen that in Examples 1 to 6 in which the photoreactive group is introduced, the difference in orientation azimuth before and after AC driving is small, and the afterimage characteristics are remarkably improved as compared with Comparative Example 1. Also. In Examples 1 to 6, the liquid crystal alignment was also good. In Examples 7 to 11 using various diamines and Examples 12 to 14 using BODA as an acid dianhydride, the afterimage characteristics are more remarkable than Comparative Example 1 using a side chain diamine. It was found that the liquid crystal alignment performance was improved. From these facts, it was found that the photoreactive material using the main chain type diamine is superior to the liquid crystal alignment regulating ability than the side chain type diamine. Therefore, by using the liquid crystal aligning agent of the present invention, a liquid crystal alignment film excellent in liquid crystal alignment and afterimage characteristics can be obtained. And since the liquid crystal display element which has the liquid crystal aligning film obtained from the liquid crystal aligning agent of this invention is excellent in liquid crystal aligning property and an afterimage characteristic, it is set as a liquid crystal display device which a display defect, a contrast fall, and a burning hardly occur. be able to.

Claims (5)

A diamine represented by the following formula (1):

(Equation (1), X ¹ is a single bond or an alkylene group having 1 to 6 carbon atoms (, -CH 2 nonadjacent of the alkylene group _- an ether bond, be replaced in an ester bond or an amide bond X ² is —OCO—CH═CH— or —CH═CH—COO—, X ³ is a single bond, an alkylene group having 1 to 10 carbon atoms, or a divalent benzene ring, ⁴ is a single bond, —OCO—CH═CH— or —CH═CH—COO—, and X ⁵ is a single bond or an alkylene group having 1 to 6 carbon atoms (provided that —CH _{2 is} not adjacent to the alkylene group). -May be replaced by an ether bond, an ester bond or an amide bond, provided that the formula (1) has one or more cinnamoyl groups.)   A polymer comprising at least one selected from a polyimide precursor obtained using the diamine according to claim 1, a polyimide obtained by imidizing the polyimide precursor, and polyamide.   A liquid crystal aligning agent comprising the polymer according to claim 2.   A liquid crystal alignment film obtained using the liquid crystal aligning agent according to claim 3.   A liquid crystal display element comprising the liquid crystal alignment film according to claim 4.